Metamagnetic effects in epitaxial BaFe<Subscript>1.8</Subscript>Cr<Subscript>0.2</Subscript>As<Subscript>2</Subscript> thin films

Epitaxial BaFe<Subscript>1.8</Subscript>Cr<Subscript>0.2</Subscript>As<Subscript>2</ Subscript> thin films with the tetragonal c-axis perpendicular to the thin film surface were grown on (LaAlO<Subscript>3</Subscript>)<Subscript>0.3</Subscript>(Sr<Subscript>2</ Subscript>AlTaO<Subscript>6</Subscript>)<Subscript>0.7</Subscript> (LSAT) single crystalline substrates using pulsed laser deposition (PLD). Resistive measurements indicate the existence of two transitions at temperatures of about 80 K and 40 K. The transition at 80 K is attributed to the structural transition from the high temperature tetragonal phase to the low temperature orthorhombic phase accompanied with the magnetic transition from a paramagnetic to an antiferromagnetic state as known for doped bulk systems. Below T ≈ 40 K the magnetization curves measured perpendicularly to the orthorhombic c-axis in fields up to 9 Tesla show two inflexion points indicating metamagnetic transitions. Copyright EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2012